Single Americans often get the short end of the stick when it comes to money. 

Living alone means shouldering the costs of all necessities on your own. And while bills for things like food and utilities may be lower for one person than two or more, costs for big-ticket items like rent don't get cut proportionally for households of one. 

Still, a growing share of U.S. adults are making it work on their own. Nearly 28% of American households are people living alone, according to the U.S. Census Bureau's 2020 estimate. That's up from about 8% of households in 1940. 

While it's a challenge for some to make ends meet on their own, for others it appears to be a boon to only be responsible for one person's living costs. 

In Suffolk, County, New York, the median household income is $119,253 and a single-person household earning that much should have nearly $60,000 left over after paying for basic necessities like housing, groceries and health care, according to a recent SmartAsset analysis. 

But a family of three — two adults and one child — earning the same amount would come up $3,883 short of meeting their needs, SmartAsset found.

The personal finance website used income data from the University of Wisconsin's County Health Rankings program and cost of living estimates from Massachusetts Institute of Technology's Living Wage Calculator to determine how much money Americans with median household incomes would have left after covering their essential bills. 

Notably, this analysis uses median household income, which could include any number of earners. The median annual salary for individuals, nationally, is just below $62,000, according to the Bureau of Labor Statistics.

Here's where single adults earning the median household income have the most disposable income:

1. Fairfax County, Virginia

• Disposable income: $83,875
• Median household income: $144,632

2. Santa Clara County, California

• Disposable income: $81,883
• Median household income: $150,502

3. Nassau County, New York

• Disposable income: $77,600
• Median household income: $135,528

4. San Francisco County, California

• Disposable income: $75,587
• Median household income: $135,366

5. San Mateo County, California

• Disposable income: $72,264
• Median household income: $143,795

6. Collin County, Texas

• Disposable income: $62,193
• Median household income: $113,943

7. Bergen County, New Jersey

• Disposable income: $62,155
• Median household income: $113,885

8. Alameda County, California

• Disposable income: $61,806
• Median household income: $121,190

9. Montgomery County, Maryland

• Disposable income: $61,610
• Median household income: $118,020

10. Suffolk County, New York

• Disposable income: $59,703
• Median household income: $119,523

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